This invention relates generally to a paintball loaders and, more particularly to an electro-magnetic induction drive mechanism for rotating a feed cone in an active feed paintball loader.
The sport of paintball war games continues to grow in popularity. During these war games, participants shoot frangible plastic balls full of a liquid dye at their opponents. The games are sometimes intensely competitive, requiring a participant to aim a gun, known also as a marker, at an opponent while pursuing, fleeing, dodging, or running for cover. Participants are excluded from further play once they have been hit and marked by a paintball. Success in the game requires the capability to fire a large number of paintballs in a short amount of time. A participant might discharge between several hundred and one thousand or more paintballs during the typical game lasting only a few minutes. Success in the game also requires player agility, which include being able to move run, dive, and roll for cover while carrying the marker.
Agitating paintball loaders are well known in the art of paintball sports, and operate by having a paintball agitator advance balls from the bottom of a loader into an outfeed tube. Active or force feeding paintball loaders are technologically advanced loaders that use powered drivers to forcibly drive paintballs from the loader, into an outfeed tube, and into the breech of a paintball marker. Examples of such loaders can be found in U.S. Pat. Nos. 6,213,110, 6,502,567, 6,701,907, and 6,792,933. As paintball loaders have evolved into electronically controlled devices capable of actively or forcibly feeding increasingly greater numbers of paintballs (at or more than 25 balls per second) into a paintball gun, the demands upon the feed apparatus in such loaders has increased accordingly.
One problem now arising in such active paintball loaders is limiting the loader feeding apparatus at times when no paintballs are being discharged from the paintball gun (zero demand from the loader). The loader drive mechanism must either temporarily suspend actuation of the feeding apparatus or risk rupturing the paintballs in the loader, the latter condition rending the paintball loader, and indeed the entire marker, effectively inoperable.
One known method for intermittently actuating the feeding mechanism is to incorporate a torsion spring into the drive apparatus for the paintball feeding mechanism and control operation of a motor drive such that it is intermittently operated in response to firing of the paintball marker. Rotation of the drive motor winds the spring which, in turn, causes the feeding mechanism to rotate when possible, such as when a paintball moves from the feeding tube into the marker's firing chamber. Such devices require complex controls to sense marker firing and manage operation of the drive motor. Additionally, once the spring is fully wound, engagement of the drive motor may cause a jammed paintball to rupture unless the torque output of the drive motor is somehow limited.
Another known method is to interpose a friction clutch between the drive motor and the feeding mechanism to limit the torque transfer to the feeding mechanism. The problem with friction devices is that torque transfer capability tends to vary as the friction surface wear. While this method might prevent unintentional paintball rupture since torque transfer is at a maximum when new friction surfaces are used and decline from that time on, the torque transfer capability will eventually become insufficient to urge paintballs from the loader to the marker as the friction materials wear. The wear time may be extended thorough use of an intermittently rotating drive motor, but such an approach requires the complicated motor controls similar to those used in the spring-based feeding mechanisms.
The above solutions are subject to breaking, wearing, or require cumbersome fixed magnet adjustments. Existing loader technologies use a traditional, brush-commutated, DC motor. This motor accepts a DC voltage causing electromagnets (much like the brushless DC design) to interact with permanent magnets. Unlike the brushless DC design, as this interaction takes place through motor rotation, components called brushes make and break connections to cause the polarity of the electromagnets to continuously cycle between positive and negative. This changing of polarity constantly pushes and pulls on the permanent magnets causing the motor to spin. Power is lost in the brushes, heat is generated from the lost power, the motor must spin at high speeds, and be reduced mechanically to produce the desired torque, and the torque is difficult to control, necessitating the mechanical components of ratio reduction and mechanical clutches.
It would therefore, be a great advantage to provide an electronically controlled drive apparatus for a paintball marker feed cone based on a brushless DC design, including micro-stepping capability, capable of providing easily manageable torque transfer capability whether used to continuously or intermittently operate the feeder mechanism. Still further advantages would be realized if the torque transfer capability of the apparatus could be selectively altered by a user to suit specific conditions, including reversing the direction of rotation to clear jams. By controlling the torque transferred through the drive mechanism, inadvertent paintball rupture can be reduced if not eliminated.